discopotato03

I don't really understand the following that these GTRS's have on an RB26 , I cant see the point of extra capacity to excite turbo's that are so so to start with . 2530's would have far better response than GT-RS's (GT2871 52 trim's) so what gives ? If someone went to the same lengths with these turbo's (2530) as WilliamsF1 did with GT-SS's surely the torque at the wheels would be adequate and very progressive . I think Gary mentioned some good times with them but cant I remember the numbers . Cheers A .

You can't but the costs involved in tooling up for two types is quite expensive if one will do . However , look closely at the outlet in those pics . The exhaust outlet hole comes much closer to the seal groove than in the pics of the previously posted 2835 Pro S . The "3037" pic is not good enough to tell if the outlet is a conical or tapered bore either . I would like to know if it's the 87 ARR housing as this would have to be a different casting to the .68 ARR . High res pictures needed of HKS GT3037 Pro S .87ARR needed . Edit : HKS USA site only shows the 2835 Pro S withe the 84 trim "cropped" GT30 turbine (51.8mm exducer ) they must not use the 90 trim version of it . The 3037 Pro S uses the normal GT 30 turbine with its 55mm exducer so 3.2 mm difference . Really need to know the housing ARR of that 3037 . Cheers A .

More than 9 less than 10 , yes been in a few magszine articles out here . I'm not sure what you call a "Watanabee" but mine have Rays Engineering stickers in them and are model specific ie right on the money offset wise . They had 205 55 fronts and 225 50 rear tyres which is better than wider fronts with wrong wheel offset . I defy anyone to get more rubber on the road without lots of caster and just a smidge of negative camber . Turn in is far better than any strut Nissan I've ever driven . With the 205's it easily has more grip than the back which is the next area to mod provided the Bluebird power rack conversion dosen't get in the way . If anyone wants a clean DR with a bit of history it's up for grabs , I want what I paid for it . Cheers A .

Actually I prefer my Vulks in 16x7 and 8 , more of a period look and very light for their size + rubber more affordable . Don't know if it was imported with them or fitted by Bem Ellis when he owned it but cheers to whom ever .

The std GT30 turbine is supposed to measure 59.9mm while the cropped version is around 56.6 . So if the difference is 3.3mm and half that on the radius , the ARR's being the same would be quite a coincidence . Actually thinking about it the area to radius ratio involves the cross sectional area at any point in the volute and the radius from the centre of that point to the housing centre or turbine shaft axis as a ratio , so turbine OD may not hve much say . Nozzle depth would change though . Pictures should show any difference . Cheers A .

I reckon its worth trying the 1.06 housing , gotta get more out than you put in . A .

Brett Lloyd from GCG Turbos once said he could get them for around six to eight through HKS , but this was a while back pre trade agreement . Is your turbo a 3037/GT30R ? Cheers A .

Yes Id like to see the turbos exhaust outlet as well . Since the 2835 and 3037 Pro s turbos use the same ARR turbine housing sizes they're probably the same , with a different profile machined inside them to suit the respective turbines . The pictures previously posted (many thanks) of the 2835 Pro S show the amount of effort HKS went to with the waste gates exhaust path . Its been sculpted to help flow down stream of the disc valve - and if its 45mm that's definatly adequate ! I hope to see more of these housings sold separatly or as a Garrett dealer option for Garrett turbos . A bit more expensive but cheaper than aftermarket manifolds and external gates . Cheers A .

I am curious to know what form of GT3540R you are using and what style of waste gate . Others here have got more but exhaust restriction was delt with ie better manifold such as the cast HKS . If by chance you're using the XR6T style GT3540R the T04E family compressor cover it may have reached its flow limit . In this case you need the T04S comp cover and adapter ring/backplate that the generic GT3540R comes with . Its a good idea to compare exhaust manifold pressure to inlet manifold pressure at full boost . Don't be surprised if the exhaust manifold pressure is significantly higher indicating a restriction to flow . Testing at the exhaust manifold will show any ills in the entire exhaust system . I'm sure many would like to know AFR and timing under full load as well . Best of luck , cheers A .

For anyone thats interested the two Dash 7 GT28R's come up almost line ball with the GT3540R in 1.06 ARR turbine housing form for compressor and turbine flow . The GT28R's (2860R's) have a little more turbine efficiency (75 vs 72%) and flow a little less at lower exhaust gas pressure ratios . I think HKS GT-SS's use a slightly different comp wheel and the maps would be interesting to compare . Cheers A .

That compressor map shown above is not applicable as its tip height is greater than most of the other 60mm compressors . It also comes std with a .60ARR T04B compressor cover - in old speak its known as the GT28RS . It does not use the "compact style" GT28 exhaust housing intended for RB26's . Cheers A .

The actuator sets the minimum boost pressure so it needs to be rated at whatever minimum you need . Electronic control is good for solving boost creep problems but cannot regulate at less than the spring pressure in the actuator can , only more . I would use the electronic control before the higher rate actuator . Cheers A .

Top thread , its good to see engine development that goes way beyond big turbos and filthy rich AFR's . I'm sure its a challenge to get good power (torque) over a wide range from limited capacity and forced induction . The individual I've had most to do with also does not like rich AFR's and I get the feeling that the "bit more fuel through it just to cool the engine" theory may have come from the carburettor/mechanical advance ignition days . An EFI system (production style) usually injects close to the inlet port so I'd imagine the evaporative cooling effect would be little if any before the charge reached the cylinder through and round hot ports and valves . With carburettors the inlet system is what some call a wet system (everything downstream of the carby has fuel and air) so I suppose there was more time to do the charge cooling thing . AJ leads me to believe that rich mixtures are more likely to enhance detonation and not going to help either your hip pocket or ring/bore life . Is there someone here that can explain why this rich thing is ie burn rate or excessive carbon or whatever . My own very limited experience proved to me that leaner 12.5/13:1 max gave best performance but timing was critical and very much tied to charge temps . My own theory is minimal exhaust restriction helps reduce reversion with its charge poluting and pre heating effects . More people are looking at high lift short timed cams to make engines breathe well in the mid range where most engines are much of the time . In David Vizards later books he talks about cams like these in the BMC A Series (dinosarur I know) , where lots of development means the performance of yesterdays race cams can be streetable today . He quotes an example of the old BMC Road rally Cam (648) being 300/300 x 394" lift . It had 300 deg on the seat timing with 244 deg at 50 thou lift . A later type Crane "tight lash" profile has 286 deg on the seat and 252 deg at 50 thou . What this means is the Crane cam has 14 deg less seat timing but 8 degrees longer duration at 50 thou which tells us that the opening rate is much faster . So I reckon more valve lift (the valve is usually the greatest restriction in the port) and shortish duration to help trapping efficiencies . Shorter timed cams set up with a little less valve overlap should help with reversion . Fast opening rates would help cylinder charging and free flowing turbine/housing/exhaust reduce the reversion problems . It sounds like you're engine is making very efficient use of its air and fuel to make bulk torque over a wide range without towing a fuel tanker around . I'd like to PM you about workshops you've used in southern Sydney as my mechanic is now out of reach . Cheers A .

Was the R30 R200 used in the 2800GT , and does the late suppliment show it ? Cheers A .

FATGTS-R that tends to be the real world experience . The problem was heavy (for their size) turbines and oil shear drag from bush bearings with their excess contact area compared to ball bearings . Exhaust housings had to have smaller ARR's to overcome the drag and innertia and give a reasonal boost threshold . The problem is this then limits total gas flow creating thermal and detonation dramas (reversion/polution/charge heating) . Modern turbos use low friction bearings and low innertia rotating group which require less exhaust eneregy to get them going . Turbine housings have come along in leaps and bounds , the modern ones have less surface flow losses and the gas retains more enery by being ducted through wider nozzles . If you compare A T3 turbine to a GT BB turbine (eg GT30) the tip heights (the inducer where the gas is fed into the blades is quite high or wide) are much greater on the GT's . The earlier designs were trying to harness the exhaust energy from low or narrow tip height inducers and the exducer section tended to wrap around more than the GT's to gain a little more trapping efficiency . The narrow nozzle of the earlier types tended to speed up the gas flow more so and the partially avoidable restriction cost the turbine some energy and the housing some flow for its size . Its easy to think that the old dinosaurs are easy and cheap - but if you were buying them brand new the price difference is often small compared to the newer ones once they're in place . Cheers A .

I've seen some real dodgy T3/T04 hybrids so make sure what you get is reasonably well thought out . The most I would ever do to the VL spec dinosaur T3 is go up to the last size ie 60 to 65 trim T3 compressor as its the turbine thats lacking and definatly not designed to power T4 comps . Avoid eight bladed T04B compressors at all costs as they are low speed surging dogs . If you must use a "B" wheel use a six bladed one as they have some chance of working - kind of . I doubt an RB20 will thank you for a bush bearing turbo , the oil and optional water fittings are all different as is the actuator waste gate and outlet pipe . The fiddly bits make it an expensive conversion . It goes against the grain but something like a GT28RS in the RB25 exhaust housing will at least bolt up to everything on the hot side . Oil water and air plumbing are not std but what else is ? I'd be thinking about the std turbo with the RB25 exhaust housing or the complete unit if its on a cheap budget . Cheers A .

Cheers .

Is that the way you'll go Cubes and yes mileage is important to me as well , hence pedalling on loan G11 Charade - true king of three cylinder carby n points terrors ! I can well understand why JE had heaps of fun in the turbo Mira . Beware of the flying flea cheers A .

Dennis the other things were called TB03's and can be found on things like the non RS500 Sierras and some US spec cars . Their turbine /housing was later technology (lighter/better aero) still used .48 ARR but better technology . It wont look like L20A or FJ T3 plus dump pipe will will look non std . L20A 's are difficult to get good turbine response from with dinosaur era turbines and bearings because of small cylinder capacity and cylinder head/manifolds designs . Have to go now got a train to run up to Syd . Cheers A .

Fair enough , most use MAP load sensed management . The factory chose Vane type or Hot Wire sensors for their accuracy . The vane type was made under licence from Bosch and was use to measure the mass of the airflow , the temp sensor should be in the AFM unit . The Hot Wire AFM is the most accurate and needs no temperature compensation because its part of the signal it generates . Load sensing from MAP runs into problems with pressure pulses . If atmospheric pressure is reached before full load (NA) all you have is the rpm signal to tune with . Running throttle bodys shows this up all the time and TPS (even more crude) or MAF is the only answer . The aftermarket manufacturers seem reluctant to go to MAF technology which is a pity because there are definate advantages . There is no lack of quite high capacity MAF sensors , the GTR brigade often use two like Nissan did . Cheers A .

Whats the damage for the 3.5 long nose with 12mm bolts ? Cheers A .

If the boots and CV's are good the diff's a bonus . DR30 R200 half shafts are desirable because they're among the shortest available . Cheers A .

Yes that is an option but MAP cannot measure mass (mass or weight of air inhaled and temperature dependant density) so its difficult to tune for all eventualitys . Manifold pressure is not a good indication of engine load or air flow . Your call .

That is off a DR30 FJ turbo , if the exhaust housing is .63ARR its the early non intercooled type . The give away is the actuator mounting bracket and the O2 probe hole in the exhaust housing . The fact that the waste gate flap valve plate is separate from the dump pipe elbow means its Skyline not S12 . The S12 manifold put the turbo higher and further forward , the S12's dump reaches lower (longer) and the dog leg in the oil drain pipe is not as extreme . That exhaust housing is desirable to those who like hybrid T3's for the same reason the VG30 housing is desirable to ceramic BB RB owners . The thing is model specific to the R30 FJ20 and fits Z18's , don't know about L6 turbo because I've never seen one . T3's really are dinosaurs mainly because of wheel design particularly the turbine/housing . Unfortunatly Nissan used the small OD turbine variety and their own design of housing and gate because it was a bit more compact than the generic Garrett/Ford style most other things used in the era . The largest of their family was the VL model Garrett/Nissan T3 for a low compression (7.8) low boost (about 5 lbs) 3L (180 cu in) 150 Kw engine . At least that version is an OEM so a known quantity , I can look up with better dinosaur variations but cost's get beyond the VG30 BB for inferior results . Engineering over design always costs more and does not always give a better result . Cheers A .

You have a long nose 3.5 , what crownwheel bolt size ? Cheers A .